EGT In The Climb

[HopePilot]

Hello,

Sorry to start a thread not dealing in bodily functions, but I was wondering what EGT number people are leaning for in the climb (i.e. that would work out to 100 degrees rich)?  

[Jeff_S]

This has been addressed a few times but always bears repeating. For the best treatise on this, go to this webpage and download the Target EGT presentation from Advanced Pilot Seminars. It will tell you how to measure it for yourself.

I haven't done this at sea level yet for my Mooney but I may try this weekend at Jekyll Island. In the meantime, since I have a JPI-700, I will typically start to lean above 3500' and just lean until I'm keeping about one bar visible for CHT on each cylinder. This generally keeps EGTs in the low-mid 1200's and keeps CHTs well below 350 so while I might could lean more aggressively I think it's a decent trade-off.

[HopePilot]

I've been leaning for 1300 (shortly after takeoff), but I think I'm too rich...

[N201MKTurbo]

Just be careful out there. If you fly enough you are bound to do something stupid eventually. For me it was leaning the mixture while on a long taxi and then getting distracted and forgetting to enrich the mixture for takeoff. After taking off scanning for traffic and dealing with the airport environment, I scanned the engine gages and noticed the CHT pegged!

The plane made it home burning about 1 QT/hr. It is kind of embarrassing to stop for fuel and ask the line man to add 4 QTs of oil. All four pistons had elongated the piston pin hole by about .005 and all the ring lands were deformed. I had softened all four pistons. It cost about $2000 to fix it.

The point is - don't be to aggressive leaning in a climb.

 

[Jeff_S]

Quote: N201MKTurbo

Just be careful out there. If you fly enough you are bound to do something stupid eventually. For me it was leaning the mixture while on a long taxi and then getting distracted and forgetting to enrich the mixture for takeoff. After taking off scanning for traffic and dealing with the airport environment, I scanned the engine gages and noticed the CHT pegged!

The plane made it home burning about 1 QT/hr. It is kind of embarrassing to stop for fuel and ask the line man to add 4 QTs of oil. All four pistons had elongated the piston pin hole by about .005 and all the ring lands were deformed. I had softened all four pistons. It cost about $2000 to fix it.

The point is - don't be to aggressive leaning in a climb.

 

[danb35]

If you were able to apply take-off power, you weren't leaned enough--proper taxi leaning is so lean that the engine will just stumble when you do your run-up.  That way, the mistake of forgetting to enrich the mixture is impossible (or at least has minimal consequences).

For leaning in the climb, note your EGTs at full power, full rich, sea level, and lean to that number as you climb (every thousand feet or so).  For me, it's about 1250 deg., but your installation will likely vary.  I doubt that 1300 deg. is too rich, but it's possible that it's too lean.